"I asked her about Dancing With the Stars and she said, 'Well, initially I'm thinking no. But let me go to school and talk to Ashley about it. See what she thinks.' I was like, 'No, Coco, you can't tell anybody! I'm sworn to secrecy.' Hopefully I don't embarrass her."

Paired with pro KymJohnson, Arquette -- who celebrated 245 days of sobriety Wednesday -- said he's got a lot to learn before the show premieres.